Mark w



(No Model J.

M. W. DEWEY.

METHOD OF ELECTRIC METAL WORKING. I No. 408,875. Patented Aug. 13, 1889.

ATTORNEYS UNITED STATES MARK XV. DEM EY, OF SYRACUSE, NEXV YORK,ASSIGNOR TO PATENT OEEIcE.

THE DElVEY CORPORATION, OF SAME PLACE.

METHOD OF ELECTRIC METAL-WORKING.

SPECIFICATION forming part of Letters'Pat-ent No. 408,875, dated August13,1889. Application filed ilune 3, 1889. Serial No. 812,973. (Nomodel.)

To aZZ whom it may concern- Be it known that I, MARK WV. DEWEY, ofSyracuse, in the county of Onondaga, in the State of New York, haveinvented new and useful Improvements in the Method of ElectricMetal-\Vorking, of which the following, taken in connection with theaccompanying drawings, is a full, clear, and exact description.

My invention relates to a new method of IO metal-working, in which boththe heatingpower of the electric current or currents and magnetism areutilized. The magnetism is for the purpose of creating electric stressor resistance in the metal at the part desired [I 5 to be heated, andthe electric current for heating the partwhere the resistance iscreated.

In electric metal-working, particularly inv operations appertainingtoupsetting, separating, or forming metal bars or plates intermediatc oftheir length into various shapes, an enormous volume of current isrequired to raise the metal to a suflicient working temperature,especially when said -bars or plates are of large cross-section andoffer a very low resistance to the current. On account of the lowresistance of the bar it is necessary,

in order to locate the heat in the same, to make the other portion ofthe circuit of very large red or cable of superior conductivity.

3o This rod or cable is usually made of copper, and because of itsexpensiveness the current generator or transformer must be located inthe immediate neighborhood of the operations.

As the heating effect of an electric current in a conductor depends notonly upon the volume of the current but also upon the resistance of theconductor, the greater part of the heat of the current will be locatedin that part of the circuit having the greater resist- 4o ance. Inwelding operations the resistance can be more easily attained, as theimperfect contact between the two pieces creates the resistancerequired; but when a large continuous bar of metal of good conductivityis to be heated intermediate of its length it is necessary, as beforevstated, to form the other portions of the circuit of conductors of lowerconductivity than the bar and generate an immense volume of current inthe circuit. A

very small increase of resistance in a part of a low-resistanceconductor will aid greatly in developing the heat generated by a currentin the conductor at that particular part. Therefore by increasing theresistance by subjecting the 'part to be heated to magnetism or magneticstress I am enabled to heat a larger bar with a given current and sizeof conductors connected to the bar than heretofore; or

it is possible to heat abar of metal with less current and smallerorless expensive conduct- 6o ors than by the usual method. Theresistance effect depends of course upon the strength of the magnetismand the arrangement of the poles of the magnet in relation to the bar orblank, which relation in turn depends upon the nature of the metal.Greater effects are found in paramagnetic metals,'as iron, nickel, &c.but good effects are found in diamagnetic metals when the poles of themagnet are arranged in proper relation to the blank of such metal, ashereinafter described.

With iron or nickel the magnetic effect is m'l when the iron isheatedtoredness ,butthe source of magnetism (the magnet) may be removed then orbefore this temperature is reached, as it has accomplished its purposeby creating stress or resistance, and thereby locating the heat in apart of the blank which may then be heated still more, if desired, forthe heat itself has produced the required re- So sistance in the bar,which resistance will be maintained and increased by continuing thesupply of current. The magnet is removed when its effect is m] or nolonger necessary, for the purpose also of relieving it from the 8 5intense heat, and removing the obstruction which it would form duringthe further Working or treating of the blank. In some diamagnetic metalsthe magnetic effect is continued during the entire heating operation toretain the resistance at the part heated, otherwise the part would tendto become cooler upon continuing the application of the current. Again,in order to locate the heat at a particular portion of the in etal-bar,the clamps 9 5 have heretofore been placed at each side of the part andthe entire portion of the bar be tween said clamps has been heated. Thisis obj ectionable in many cases, as when the clamps are placed closetogether, in order to I00 locate the heat in a small portion of the barthat requires a forming, shaping, or other operation, while the currentis still flowing andv the clamps are in the aforesaid position. Thisdifficulty is obviated by my method, which allows the clamps to bewidely SOPZULtOtl on the bar, the heatlocated at any point or pointsalong the said bar between the clamps, the same being, preferably,flexibly connected with the circuit, and permits of free and unhamperedworking of the heated portion, and, further, the clamps themselves arenot overheated.

My invention consists, essentially, in subj ecting the entirecross-section of a blank to a magnetic held of uniform strength, and simul taneously therewith passing through the blank, including the saidi'nagnetized part, an electric current of suilicjient volume to softenthe said part, and then working or treatin the part as desired; or itconsists in subjecting the part of a blank to be worked or otherwisetreated to a magnetic held and simultaneously therewith subjecting theblank, including the said part, to the heating action of an electriccurrent of suitable volume flowin g in a direction different from thedirection of the lines of force in the said. magnetic field, and thenworking or treatingthe said part as desired; and my invention furtherconsists in subjeclin the part of ablank to be worked or otherwisetreated to a llllgllOlQlO field, and simultaneously therewith subjectingthe blank, including the said part, to the heating action of an electriccurrent of suitable volume, having its direction at rightangles, orsubstantially at right angles, to the direction of the lines of force inthe said magnetic field, and then working or treating the said blank asdesired.

In the accompanying drawings, liigure 1 illustrates one of thearrangen'ients for accomplishing the herein described method, whereinalternatingcurrents are supplied both for magnetizing and heating thebar. Fig. is another form of the same wherein the alternating currentssupplied to the magnets are rectified or straightened. Fig. 23 shows amagnet with a laminated. core that may be used when alternating currentsare employed. Fig. =1: shows the poles of a magnet shaped to correspondto the form of the bar. l ig. shows a permanent magnet applied to a bar;l ig. (3, another arrangement of the magnet in relation to the bar;lJig. 7, an electro-magnetic tongs. Fig. 8 shows the arrangement of abar having an OIllHl'gOlllOllli to be heated above the temperature ofthe neighboring portions between theclainps, and Figs. fl and 10 showtwo elevations of apparatus for mag netizing a plate.

ieferring specifically to the drawings, A in Fig. 1 .I'CPI'CSClllS analternating dynanu), A and A the comluctors leading therefrom, includingan adjustable resistance ii to regulate the current, and the primarycoil of an ilHlllCliOllfll transiknmer As usual with such apparatus,theprimary current is oi. high tension and small volume, andistransformed by a suitable transforimnf into a current having oppositequalities-awn, low tension and great volume which flows in the secomlarycircuit C of saidtransformer. The said transformer is in this case thesource of the heating-current. D is the bar or blank of metal to beheated and worked, and is connectedby suitable clamps c-iin this case (1and. (-.with the terminals of the secondary circuit, which is preferablyformed of a flexible conductor or comluctors of low resistance. l is anelec ire-magnet arranged. with its poles on oppo site sides of the barat or near the point to be heated. The object in thus arranging thepoles of the magnet in relation to the bar is to change the position ol.the molecules in the bar, so that they will lie. in a positiondill'erent from that in which the current places them. (L and a are thecoils of the magnet, and are shown in a shunt-circuitl! of the primarycircuit. f is an. adjustable resistance in the shunt to control thecurrent therein. The upper pole of said n'iagnet and coil. (1 is madeadjustable vertically, so that the poles may be separated more or lessto admit bars between them of different. diameters. Although the polesmay come in contact with the bar, better effects are obtained when theydo not touch the bar, but are held in close proximity to the same, asshown. liy increasing or diminishing the current in the shunt orseparating the magnets more or less the resistance may be regulated asdesired.

Fig. 3 is the same as llig. l, with the I'olh'nw ing exceptions: Thecurrent of the magnet is rectified or straightcnedv in any suitable manner, preferably as shown in patent to Westinghouse, No. 3713,0 35, datedNovember s, lStW. G indicates the straightening device. The magnet issulfiported adjustably in. any suitable position in relation to the bar,aml may be removed entirely, when desirm'l, by means of the jointed armb. ()no of the clamps is stationary, and the other 0 mover bio andflexibly c n'|ieeted with the secondary circuit so that if endwisepressure or drawing or pulling is the operation to be per" formed uponthebar after it is heated it may be accomplished by moving the clamp cby meansof the screw d. It will be obvious that both the transformer andreetiiiinti may be dispensed with when a continuous directhcating-current is employed, and also that the magnets maybe suppliedwith current from a separate source from that supplying theheating-currenl.

Fig. 53 shows an eleetrommgnet having a laminated core 0 and a singlecell (I and bar 1) in. position. it is )l'(3i t)l'l'(,(l. to have thecore laminated or formel'l of insulated wires when the magnet isenergixml by alternating currents, so that the core will not becomeheated.

Fig. 4 shows the magnet provided with polepieces 1' i, shaped tocorrespond to the forn1- other figures, where the poles of the magnetsare at diametrically-opposite sides of the bar. Better effects can beobtained with some metals, especially diamagn etic metals by this or asimilar arrangement, as the molecules are then in a position to offerthe greatest resistance to the current.

Fig. 7 shows a pair of tongs provided with coils a and a, forming anelectro-magnet, and a bar D in position between the poles.

Fig. 8 represents a bar or blank. D, eonnectcd with clamps c and c, andflexible connections g g, so that the bar while in circuit and thecurrent flowing through it may be handled, forged, and worked as desiredoperations that could not be effected when held in the apparatus shownin Fig. 2such as twisting, bending, the. The said clamps or electricalconnect-ions .in this case are not rigidly connected with each other, asshown in Fig. 2, but are capable of universal movement independent ofeach other to allow the blank to be handled and formed in any desiredshape while connected with the clamps. The bar, when thus flexiblyconnected in the circuit, may be held while heated by suitable insulatedsupports, clamps, or tools, stationary or movable. The figure alsorepresents an enlarged portion h of the bar desired to be heated inexcess of the other portions of .the bar between the clamps in positionbetween the poles of a magnet.

Figs. 9 and 10 represent two views of an elongated electro-magnet formagnetizing a plate to be heated and worked, Z and Z indicating theconductors of the heating-circuit.

It will be obvious that it may be advantageous to employ magnetism insome cases for all forms of electric metal-working, ineludin g welding,tempering, &c.

For the sake of simplicity, it will be suflicient for the purpose ofthis invention to suppose that in all cases magnetizing the conductorcauses the same to offer higher resistance to the current, and althoughit may be ultimately found in some cases to have the opposite effect,yet in all cases said magnetization will localize the heat produced bythe current at or near the altered part, and, as is well known, afterthe heat is once located it will itself offer an increased resistance tothe current and rapidly develop itself.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is

1. The herein-described method of metal working, consisting in creatingelectric stress or resistance in a continuous metal bar or blank bysubjecting the blank at or near the part to be worked to magetism andsimultaneously therewith passing through the blank, including the saidpart, an electric current of sufficient volume to soften the said part,and then bending, shaping, or otherwise working or treating the part.

2. The herein-described method of metalworking, consisting in subjectingthe blank at or near the part to be worked to the action of a magneticfield and simultaneouslytherewith subjecting a portion of the blank,including the said part, to the heating action of an electric current ofsufficient volume to heat the said part, removing the source ofmagnetism when its effect is all, and continuing to supply said currentuntil the part is sufficiently softened. and then working or treatingthe said part as desired.

3. The method of metal-working, consisting in creating electric stressor resistance in a metal bar or blank connected in circuit by subjectingthe part of a blank to be heated and worked or otherwise treated tomagnetism and simultan eously therewith passin gthrough said blank,including the said part, an electric current of suitable volume, andthen working or treating the said part as desired.

4. The method of metal-working, consisting in subjecting the part ofablank to be worked or otherwise treated to a magnetic field andsimultaneously therewith subjecting the blank, including the said part,to the heating action of an electric current of suitable volume flowingin a direction different from the direction of the lines of force in thesaid magnetic field, and then working or treating the said part asdesired.

5. The method of metal-workin g, consisting in subjecting the part of ablank to be worked or otherwise treated to a magnetic field andsimultaneously therewith subjecting the blank, including the said part,to the heating action of an electric current of suitable volume, havingits direction at right angles, or substantially at right angles, to thedirection of the lines of force in the said magn etic field, and thenworking or treating the said blank as desired.

(3. The method of metalworking, consisting in subjecting the entirecross-section of a blank at or near the part to be heated and worked orotherwise treated to a magnetic lield and simultaneously therewithsubjecting the blank, including the said part, to the heating action ofan electric current of suitable volume having its direction at rightangles, or substantially at right angles, to the direc tion of the linesof force in the said magnetic field, and then working or treating thesaid blank as desired.

7. The method of in etal-workin g, consisting in creating electricstress or resistance in a metal bar or blank by subjecting the entirecross-section of a blank to a magnetic field of uniform strength andsimultaneously therewith passing through the blank, ineludin themagm'itized part, an electric current of sufficient volume to soften thesaid part, and then working or treating the part as desired.

8. The method of metal-workin g, consisting in connecting the blank tobe heated and worked in a circuit by independent universally-movableconnections, passing an electric current through the circuit ofsutlicient volume to heat or soften the blank, and then moving saidconnections and handling and working the blank as desired.

$1. The method of metal-working, consisting in clamping, by independentuniversallyanovable clamps, the bar or blank of metal. at two points,leaving-a section of themetal. between the clamps, connecting the clampsby flexible lo\\'-resistance conductors with the source ofheating-current, passing an electric current through the flexibleconductors, clamps, and section of metal between them, so as to softenthe metal, and then moving said clamps and handling and working ortreating the blank as desired.

10. The method ofmetal-werking, consisting in clamping the bar or blankof metal at two points, leavingasection of the metal between the clamps,flexibly connecting the clamps by flexible lo\\'-resistance conductorswith the source of heating-current,subjecting the metal between theclamps to magnetism and. simul taneously therewith passing an electriccurrent through the flexible conductors, clamps, and section of metalbetween them, so as to soften the metal, and then handling and workin gor treating the blank as desired.

1.1. The method of metal-working, consisting in creating resistance tothe electric current in a metal bar or blank at or near the part to beheated and worked, passing an. electric current through the bar or blankot' suflicient volume to soften the same at the part wherein theresistance is created, and then working the blank as desired.

12. The method ofmetal-working,consisti ng in flexibly connecting thebar or blank to be heated 'and worked in an electric circuit, crez'ttingresistance to the electric current in the bar or blank at or near thepart to be heated and worked, and mssing an electric current through thesaid baror blank ot' snl'iicient volume to soften. the same at the partwherein the res'stance is created, and then handling and working theblank as desired.

In testimony whereof I have hereunto signed my name this 31 st day ofMay, 1889.

\Yitnesses:

( ll. 'DUELL, II'. 'M. SEAMANS.

